To calculate the heat released during the combustion of 5 grams of propane, we first need to determine the number of moles of propane in 5 grams. The molecular weight of propane C3H8 is: 3 * 12.01 + 8 * 1.01 = 36.03 + 8.08 = 44.11 g/molNow, we can find the number of moles of propane in 5 grams:5 g / 44.11 g/mol = 0.1133 molesSince the enthalpy change of combustion of propane is -2220 kJ/mol, we can calculate the heat released during the combustion of 0.1133 moles of propane:Heat released = 0.1133 moles * -2220 kJ/mol = -251.3 kJTherefore, the heat released during the combustion of 5 grams of propane at constant volume is approximately -251.3 kJ.